"Bytting" is a child which is replaced with a kid of underground heritage. Superstitions about kids which were different, with physical, psychic or mental disorder, and often they where placed out in the woods in hope of a change back.

Byttinger

Three young immigrant boys, Wasim, Riaz and Munawar, come of age in the east end of Oslo, Norway. They find school boring and become attracted to the hard boiled gang East Side Crew, run by brothers Sadiq and Khalid. Petty theft soon develops into drug dealing, violence and murder.